v3.8.0.1
Use of Collateral (Details) - USD ($)
$ in Millions
Sep. 30, 2017
Dec. 31, 2016
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Margin deposits [1] $ 216 $ 350
Natural gas and power prepayments 27 25
Total margin deposits and natural gas and power prepayments with our counterparties [2] 243 375
Letters of credit issued 731 798
First priority liens under power and natural gas agreements 193 206
First priority liens under interest rate hedging instruments 41 55
Total letters of credit and first priority liens with our counterparties 965 1,059
Margin deposits held by us posted by our counterparties [1],[3] 19 16
Letters of credit posted with us by our counterparties 33 43
Total margin deposits and letters of credit posted with us by our counterparties 52 59
Current and Non-current Derivative Assets and Liabilities [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Total margin deposits and natural gas and power prepayments with our counterparties [2] 85 78
Margin deposits held by us posted by our counterparties 3 6
Other Current Liabilities [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Margin deposits held by us posted by our counterparties 16 10
Prepaid Expenses and Other Current Assets [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Total margin deposits and natural gas and power prepayments with our counterparties [2] 149 288
Other Assets [Member]    
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Total margin deposits and natural gas and power prepayments with our counterparties [2] $ 9 $ 9
[1] During the third quarter of 2017, we elected to offset fair value amounts recognized for derivative instruments executed with the same counterparty under a master netting arrangement for financial statement presentation; therefore, amounts recognized for the right to reclaim, or the obligation to return, cash collateral are presented net with the corresponding derivative instrument fair values. See Note 1 for a further description of the change in accounting principle associated with our election to offset fair value amounts associated with our derivative instruments. See Note 6 for further discussion of our derivative instruments subject to master netting arrangements.
[2] At September 30, 2017 and December 31, 2016, $85 million and $78 million, respectively, were included in current and long-term derivative assets and liabilities, $149 million and $288 million, respectively, were included in margin deposits and other prepaid expense and $9 million and $9 million, respectively, were included in other assets on our Consolidated Condensed Balance Sheets.
[3] At September 30, 2017 and December 31, 2016, $3 million and $6 million, respectively, were included in current and long-term derivative assets and liabilities and $16 million and $10 million, respectively, were included in other current liabilities on our Consolidated Condensed Balance Sheets.